I-Methyl Cellulose (MC) Ifomula ye-molecular \[C6H7O2(OH)3-h(OCH3)n1] x Ikotini ecolisisiwe iphathwa nge-alkali, futhi i-methyl chloride isetshenziswa njenge-etherification agent. Ngemuva kochungechunge lokusabela, ukwelashwa kwe-cellulose ether kuyenziwa. Ngokuvamile, izinga lokushintsha liyi-1.6 ~ 2.0, futhi izinga lokushintsha lihlukile. Kungokwe-non-ionic cellulose ether.
1. I-Methylcellulose iyancibilika emanzini abandayo, amanzi ashisayo azohlangabezana nobunzima, futhi ububanzi be-pH yesisombululo esinamanzi zizinzile kakhulu phakathi kuka-3/12. Isitashi, i-guar gum namanye ama-surfactants amaningi ayahambisana kakhulu. I-Gelation kwenzeka lapho izinga lokushisa lifinyelela izinga lokushisa le-gelation.
Ukugcinwa kwamanzi kwe-methylcellulose kuncike enanini elingeziwe, i-viscosity, ukucoleka kwezinhlayiyana nezinga lokuqedwa. Ngokuvamile kukhulisiwe, okuncane, i-viscosity ephezulu, ukugcinwa kwamanzi aphezulu. Phakathi kwazo, ukugcinwa kwamanzi kunomthelela omkhulu kakhulu, futhi izinga le-viscosity alilingani ngokuqondile nokugcinwa kwamanzi. Izinga lokuhlakazeka lincike ikakhulukazi ezingeni lokuguqulwa kwendawo yezinhlayiya ze-cellulose kanye nokucoleka kwezinhlayiya. Phakathi kwama-cellulose ethers angenhla, i-methyl cellulose ne-hydroxypropyl methyl cellulose anokugcinwa kwamanzi okuphezulu.
Ukushintsha kwezinga lokushisa kungathinta kakhulu ukugcinwa kwamanzi kwe-methyl cellulose. – Uma izinga lokushisa liphezulu, kuba kubi kakhulu ukugcinwa kwamanzi. Uma izinga lokushisa lodaka lidlula i-40 ° C, ukugcinwa kwamanzi kwe-methyl cellulose kuzoncishiswa kakhulu, okuthinta kakhulu ukwakhiwa kodaka.
I-Methylcellulose inomthelela omkhulu ekusebenzeni nasekubambeleleni kodaka. Igama elithi “stickiness” lapha libhekisela ekunamatheleni phakathi kwethuluzi lokufaka isicelo lesisebenzi kanye ne-substrate yodonga, okungukuthi, ukumelana ne-shear kodaka. I-viscosity, amandla okugunda udaka, namandla adingwa yizisebenzi ezisetshenziswayo nakho kukhulu kakhulu, futhi ukwakhiwa kodaka akukuhle. I-Methylcellulose ibambelele emazingeni amaphakathi emikhiqizweni ye-cellulose ether.
2. I-Hydroxypropyl methylcellulose (HPMC) [C 6 H 7 O 2 (OH) 3-mn (OCH 3 ) m, OCH 2 CH (OH) CH 3 ] n]] i-hydroxypropyl methyl cellulose Eminyakeni yamuva nje, izinhlobo ze-cellulose zine anda ngokushesha. I-ether engeyona i-ionic cellulose exutshwe i-ether elungiselelwe uchungechunge lokusabela ngemva kwe-alkalization ye-alkali kakotini ecolisisiwe, lapho i-propylene oxide ne-methyl chloride kusetshenziswa khona njengama-etherification agents. Izinga lokushintsha ngokuvamile lingu-1.2/2.0. Izakhiwo zayo ziyahlukahluka ngokuya ngesilinganiso sokuqukethwe kwe-methoxyl nokuqukethwe kwe-hydroxypropyl.
1. I-Hydroxypropyl methylcellulose ihlukaniswe ngohlobo lwe-hot-melt kanye nohlobo olusheshayo. Ukushisa kwayo kwe-gelation emanzini ashisayo kuphakeme kakhulu kune-methylcellulose. Iphinde ibonise ukuthuthuka okukhulu ngaphezu kwe-methylcellulose lapho incibilika emanzini abandayo.
I-viscosity ye-hydroxypropyl methylcellulose ihlobene nesisindo samangqamuzana, futhi isisindo samangqamuzana siphezulu. Ukushisa nakho kuthinta i-viscosity yayo, njengoba izinga lokushisa likhuphuka, i-viscosity iyancipha. Nokho, ithonya lokushisa ku-viscosity liphansi kunalelo le-methyl cellulose. Isixazululo isitoreji esizinzile ekamelweni lokushisa.
3. Ukugcinwa kwamanzi kwe-hydroxypropyl methylcellulose kuncike enanini layo elingeziwe, i-viscosity, njll., futhi izinga lokugcinwa kwamanzi lenani elifanayo lingaphezulu kwele-methyl cellulose.
4. I-Hydroxypropyl methylcellulose izinzile ku-asidi ne-alkali, futhi isisombululo sayo esinamanzi sizinzile kakhulu ku-pH ye-2/12. Ukusebenza kwe-caustic soda namanzi e-lime akunawo umthelela omkhulu, kodwa i-alkali ingasheshisa izinga lokuqedwa kwayo, futhi i-viscosity iyanda. I-Hydroxypropyl methylcellulose izinzile kusawoti ovamile, kodwa lapho ukugxila kwesisombululo sikasawoti kuphezulu, i-viscosity yesisombululo se-hydroxypropyl methylcellulose ivame ukwanda.
I-Hydroxypropyl methylcellulose ingaxutshwa nama-polymers ancibilika emanzini ukuze kwakheke i-uniform, i-high-viscosity solution. Okufana ne-polyvinyl alcohol, isitashi ether, ushingamu wemifino, njll.
I-Hydroxypropyl methylcellulose inokumelana ne-enzyme engcono kune-methylcellulose, amathuba okuwohloka kwe-enzymatic yesisombululo sayo aphansi kune-methylcellulose, futhi ukunamathela kwe-hydroxypropylmethylcellulose ekwakhiweni kodaka kuphakeme kunaleyo ye-methylcellulose. i-cellulose eyisisekelo.
Okwesithathu, i-hydroxyethyl cellulose (HEC) yenziwe ngokotini ocolisisiwe ophathwe nge-alkali, lapho kukhona i-acetone, ne-ethylene oxide njenge-etherification agent. Izinga layo lokushintsha ngokuvamile liyi-1.5/2.0. Ine-hydrophilicity eqinile futhi kulula ukumunca umswakama.
1. I-Hydroxyethyl cellulose iyancibilika emanzini abandayo, kodwa kunzima ukuyincibilika emanzini ashisayo. Isixazululo sizinzile ekushiseni okuphezulu futhi asinazo izakhiwo zejeli. Ingasetshenziswa isikhathi eside odakeni olushisa kakhulu, kodwa ukugcinwa kwayo kwamanzi kuphansi kunaleyo ye-methyl cellulose.
2. I-Hydroxyethyl cellulose izinzile ku-asidi evamile kanye ne-alkali. I-alkali isheshisa ukuqedwa kwayo, futhi i-viscosity yayo ikhuphuka kancane. Ukuhlakazeka kwayo emanzini kubi kancane kunaleyo ye-methyl cellulose ne-hydroxypropyl methyl cellulose.
3. I-Hydroxyethyl cellulose inokusebenza okuhle kokulwa nokulenga odakeni, kodwa isikhathi eside, enye i-hydroxyethyl cellulose ekhiqizwa ekhaya inokusebenza okuphansi kakhulu kune-methyl cellulose ngenxa yokuqukethwe kwamanzi amaningi kanye nomlotha omningi.
4. I-Carboxymethyl cellulose (CMC) \ [C6H7O2 (OH) 2och2COONa] (ukotini, njll.) yefayibha yemvelo iphathwa nge-alkali, futhi i-sodium chloroacetate isetshenziswa njenge-etherification agent, ngemva kochungechunge lwezindlela zokwelapha zokusabela, yenziwa i-ionic. i-cellulose ether. Izinga lokushintsha ngokuvamile lingu-0.4/1.4, futhi izinga lokushintsha linomthelela omkhulu ekusebenzeni.
I-Carboxymethyl cellulose ine-hygroscopicity ephezulu, futhi izimo zokugcinwa ezijwayelekile ziqukethe amanzi amaningi.
2. Isixazululo samanzi se-Carboxymethyl cellulose asikhiqizi ijeli, i-viscosity iyancipha lapho izinga lokushisa likhuphuka, futhi i-viscosity ayinakubuyela emuva lapho izinga lokushisa lidlula u-50°C.
Ukuzinza kwayo kuthinteka kakhulu yi-pH. Ngokuvamile isetshenziselwa udaka lwe-gypsum, hhayi udaka lukasimende. Endabeni ye-alkalinity ephezulu, izolahlekelwa yi-viscosity yayo.
Ukugcinwa kwayo kwamanzi kuphansi kakhulu kunaleyo ye-methyl cellulose. I-Gypsum mortar inomphumela wokuhlehlisa, inciphisa amandla. Kodwa intengo ye-carboxymethyl cellulose iphansi kakhulu kunaleyo ye-methyl cellulose.
Isikhathi sokuthumela: Jan-13-2023